Saturday, August 30, 2014

Seuss Crater


In the top left part of this image is Seuss, a complex crater with hollows present on the crater's floor. In this enhanced color image, the hollows appear as bright blue-white features. Just outside of Seuss' rim, you can see some material that appears darker brown in the image. This is LRM, or Low Reflectance Material, and was probably excavated by the impactor when Seuss was formed. Extending from Seuss are bright crater rays, which are streams of ejecta that were thrown from the crater upon impact. In the bottom right of the image, you can see an irregularly shaped, orange-yellow depression that could be a volcanic vent.

This image was acquired as part of MDIS's high-resolution 3-color imaging campaign. The map produced from this campaign complements the 8-color base map (at an average resolution of 1 km/pixel) acquired during MESSENGER's primary mission by imaging Mercury's surface in a subset of the color filters at the highest resolution possible. The three narrow-band color filters are centered at wavelengths of 430 nm, 750 nm, and 1000 nm, and image resolutions generally range from 100 to 400 meters/pixel in the northern hemisphere.

Date acquired: July 08, 2014
Image Mission Elapsed Time (MET): 47121909, 47121901, 47121905
Image ID: 6643252, 6643250, 6643251
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filters: 9, 7, 6 (996, 748, 433 nanometers) in red, green, and blue
Center Latitude: 2.83º
Center Longitude: 37.11º E
Resolution: 528 meters/pixel
Scale: Seuss is 64 km (40 miles) in diameter
Incidence Angle: 15.8º
Emission Angle: 12.2º
Phase Angle: 28.0º

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Landslide From a Second Impact Crater


This image features a simple crater in the northern smooth plains. Superimposed on the wall of this crater is another impact crater. The smaller crater is elliptical in shape, which is most likely due to being formed on a slope on the larger crater's wall. It also appears that this impact event caused material to slide down the crater wall, which can be seen in this high-resolution image.

This image was acquired as part of the MDIS low-altitude imaging campaign. During MESSENGER's second extended mission, the spacecraft makes a progressively closer approach to Mercury's surface than at any previous point in the mission, enabling the acquisition of high-spatial-resolution data. For spacecraft altitudes below 350 kilometers, NAC images are acquired with pixel scales ranging from 20 meters to as little as 2 meters.

Date acquired: July 19, 2014
Image Mission Elapsed Time (MET): 48103544
Image ID: 6712882
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 72.72°
Center Longitude: 313.7° E
Resolution: 17 meters/pixel
Scale: This image is about 9 km (5.5 miles) across.
Incidence Angle: 78.6°
Emission Angle: 0.3°
Phase Angle: 78.9°

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Tuesday, August 26, 2014

VIRS Tracks Over Verdi Crater and the Northern Latitudes


Today's image shows an area in Mercury's northern latitudes crossed by a series of MASCS VIRS tracks displayed as a color composite, overlain on a MDIS base map mosaic. Craters Verdi and Janáček reside in this area, along with several unnamed craters. The VIRS footprints are smaller, each covering less area, in the northern hemisphere due to MESSENGER's elliptical orbit.

The VIRS composite shows hundreds of individual footprints tracks (minimum 100-200 m across and 3-4 km long) taken from different directions and altitudes. In locations where multiple footprints cover the same area, the footprint with the best illumination for mineralogical interpretation (usually the lowest incidence angle where shadows are minimized) is used for making the map. In the MDIS mosaic, some brightness variations are due to tiling of images taken at different illuminations.

Date Created: July 27, 2014
Instruments: Visible and Infrared Spectrograph (VIRS) of the Mercury Atmosphere and Surface Composition Spectrometer (MASCS) and Mercury Dual Imaging System (MDIS)
VIRS Color Composite Wavelengths: 575 nm as red, 415 nm/750 nm as green, 310 nm/390 nm as blue
Center Latitude: 57.7°
Center Longitude: 197.5° E
Resolution: 1 km/pixel
Scale: Verdi (top left) crater is 145 km (90 miles) in diameter

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Saturday, August 23, 2014

Hollows in an Unnamed Crater


This high-resolution image features hollows within an unnamed crater. Hollows often have bright halos and usually form in or around craters. Here, the hollows are forming on the crater floor, along the base of the crater wall, and on the top of the central peak.

This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.

Date acquired: October 13, 2012
Image Mission Elapsed Time (MET): 258630853
Image ID: 2758246
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 50.63°
Center Longitude: 320.6° E
Resolution: 15 meters/pixel
Scale: This image is about 16 km (10 miles) across.
Incidence Angle: 76.8°
Emission Angle: 15.0°
Phase Angle: 91.9°

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Thursday, August 21, 2014

Three Views of Hokusai Crater


Today's image shows three oblique mosaics of Hokusai, a complex crater in Mercury's northern hemisphere. The top mosaic features a view of Hokusai where north is to the left. The bottom left is a color mosaic that also has north to the left. In the bottom right is mosaic with a high incidence angle where north is now to the right. The high incidence angle emphasizes topography differences because the sun's low angle creates long shadows. Evident in all of these mosaics are Hokusai's smooth impact melt covered floor, central peak, ejecta blanket, and terraced walls.

The top mosaic was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.

The bottom left color image was acquired as a targeted high-resolution 11-color image set. Acquiring 11-color targets is a new campaign that began in March 2013 and that utilizes all of the WAC's 11 narrow-band color filters. Because of the large data volume involved, only features of special scientific interest are targeted for imaging in all 11 colors.

The bottom right mosaic was acquired as part of MDIS's high-incidence-angle base map. The high-incidence-angle base map complements the surface morphology base map of MESSENGER's primary mission that was acquired under generally more moderate incidence angles. High incidence angles, achieved when the Sun is near the horizon, result in long shadows that accentuate the small-scale topography of geologic features. The high-incidence-angle base map was acquired with an average resolution of 200 meters/pixel.

Instruments: Wide Angle Camera (WAC) and Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
WAC filters: 9, 7, 6 (996, 748, 433 nanometers) in red, green, and blue for color mosaic
Center Latitude: 57.66°
Center Longitude: 16.58° E
Scale: Hokusai is about 85 km (53 miles) in diameter.

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Tuesday, August 19, 2014

Volcanic Vents North of Rachmaninoff Basin


This image, located north of Rachmaninoff, features a possible volcanic vent to the east and an expanse of terrain that appears blue in this color view to the west. The depression's orange-yellow color and irregular shape are similar to other possible volcanic vents on Mercury. To the west of the large vent is a crater with an orange, irregularly shaped depression on its floor that may also be a vent. Vents on Mercury are indicative of explosive volcanism that was prevalent in Mercury's past.

This image was acquired as a high-resolution targeted color observation. Targeted color observations are images of a small area on Mercury's surface at resolutions higher than the 1-kilometer/pixel 8-color base map. During MESSENGER's one-year primary mission, hundreds of targeted color observations were obtained. During MESSENGER's extended mission, high-resolution targeted color observations are more rare, as the 3-color base map covered Mercury's northern hemisphere with the highest-resolution color images that are possible.

Date acquired: July 03, 2014
Image Mission Elapsed Time (MET): 46686728, 46686748, 46686732
Image ID: 6612580, 6612585, 6612581
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filters: 9, 7, 6 (996, 748, 433 nanometers) in red, green, and blue
Center Latitude: 36.10°
Center Longitude: 54.93° E
Resolution: 215 meters/pixel
Scale: The crater with a possible vent on its floor is about 20 km (12.4 miles) in diameter.
Incidence Angle: 40.6°
Emission Angle: 39.4°
Phase Angle: 78.0°

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Saturday, August 16, 2014

Altimetry Profile of an Unnamed Simple Crater


Today's image features a small, simple impact crater on Mercury's northern plains. The superimposed track is a set of altimetry measurements by the Mercury Laser Altimeter (MLA) that resolves the bowl-shaped morphology characteristic of simple craters. This morphology is evident in the topographic profile on the right of this image that displays how the crater's depth changes from point A to point B.

Instrument: Mercury Laser Altimeter (MLA)
MLA Track: MLASCIRDRAPLFN1112211457
Crater's Center Latitude: 78.1°
Crater's Center Longitude: 327.5° E
Scale: The crater has a diameter of 4.53 km (2.81 miles)

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Thursday, August 14, 2014

Simple Crater on Rikyu Crater's Rim


Rikyü is an impact crater named for Sen no Rikyü, the master who was central in the development of the Japanese tea ceremony. Rikyü sits in Mercury's northern plains and is expected to host water ice because of its persistently shadowed interior and radar-bright signature. Today's image features a northwestern segment of the crater wall, where a 4.1 km-wide simple crater has resulted from an impact on Rikyü's rim. This high-resolution image also provides a fantastic view of the tiny craters that mark the crater's wall.

This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.

Date acquired: August 04, 2012
Image Mission Elapsed Time (MET): 252610116
Image ID: 2330144
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 80.17°
Center Longitude: 335.4° E
Resolution: 13 meters/pixel
Scale: The simple crater in the lower left corner is approximately 4.1 km wide (2.5 miles)
Incidence Angle: 82.8°
Emission Angle: 44.8°
Phase Angle: 127.6°

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Tuesday, August 12, 2014

Bright Rayed Crater


Today's color image features a small crater in Mercury's northern hemisphere. This relatively young crater is highlighted by its striking white rays, which contrast the darker, surrounding terrain of low reflectance material. The bright rays result from fine-grained and relatively unweathered material that was ejected and deposited by the impact.

This image was acquired as a targeted high-resolution 11-color image set. Acquiring 11-color targets is a new campaign that began in March 2013 and that utilizes all of the WAC's 11 narrow-band color filters. Because of the large data volume involved, only features of special scientific interest are targeted for imaging in all 11 colors.

Date acquired: July 08, 2014
Image Mission Elapsed Time (MET): 47178430, 47178426, 47178424
Image ID: 6647334, 6647332, 6647331
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filters: 9, 7, 6 (996, 748, 433 nanometers) in red, green, and blue
Center Latitude: 43.97°
Center Longitude: 34.76° E
Resolution: 348 meters/pixel
Scale: The crater on the right of this image is approximately 16 km (10 miles) across
Incidence Angle: 45.9°
Emission Angle: 1.6°
Phase Angle: 44.9°

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Saturday, August 9, 2014

Lermontov Crater by VIRS


Today's video is a MASCS VIRS raster scan of Lermontov in Mercury's mid latitudes. Raster scans return a large number of spectra for targeted areas of interest. This movie was created from 258 VIRS spectra, taken 1 to 5 seconds apart. The VIRS color composite has been overlain on an MDIS image of Lermontov, showing that the crater center is red and thus brighter at longer wavelengths compared to the average Mercury terrain.

The VIRS composite shows hundreds of individual footprints tracks (minimum 100-200 m across and 3-4 km long) taken from different directions and altitudes. In locations where multiple footprints cover the same area, the footprint with the best illumination for mineralogical interpretation (usually the lowest incidence angle where shadows are minimized) is used for making the map.

Date Observed: August 8, 2013
Date Created: July 29, 2014
Instruments: Visible and Infrared Spectrograph (VIRS) of the Mercury Atmosphere and Surface Composition Spectrometer (MASCS) and Mercury Dual Imaging System (MDIS)
VIRS Color Composite Wavelengths: 575 nm as red, 415 nm/750 nm as green, 310 nm/390 nm as blue
Initial Latitude of Scan: 14.0°
Initial Longitude of Scan: 310.8° E
Final Latitude of Scan: 17.8°
Final Longitude of Scan: 310.0° E
Resolution: 0.25 km/pixel
Scale: Lermontov is 166 km (103 mi.) in diameter

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Thursday, August 7, 2014

VIRS and MDIS Images for Kertesz, Dominici and an Unnamed Crater


The left column of images shows MASCS VIRS interpolated color composites of Kertesz (top), Dominici (middle), and an unnamed crater (bottom). The middle column shows the VIRS color composite of spectral footprints, and the left column shows monochrome MDIS images for the same areas. Yellow areas are highly reflective and thought to be relatively young, exhibiting fewer effects of space weathering. Kertesz and Dominici are also known to contain hollows, which are shallow depressions with younger surfaces likely caused by the loss of volatiles.

The VIRS composite shows hundreds of individual footprints tracks (minimum 100-200 m across and 3-4 km long) taken from different directions and altitudes. In locations where multiple footprints cover the same area, the footprint with the best illumination for mineralogical interpretation (usually the lowest incidence angle where shadows are minimized) is used for making the map. Where footprints are sparse, interpolation is required for full spatial coverage.

Date Created: July 28, 2014
Instruments: Visible and Infrared Spectrograph (VIRS) of the Mercury Atmosphere and Surface Composition Spectrometer (MASCS) and Mercury Dual Imaging System (MDIS)
VIRS Color Composite Wavelengths: 575 nm as red, 415 nm/750 nm as green, 310 nm/390 nm as blue
Center Latitudes: 27.3° (top); 1.18° (middle); -3.6° (bottom)
Center Longitudes: 146.1° E (top); 323.5° E (middle); 60.9° E (bottom)
Resolution: 0.5 km/pixel
Scale: Kertesz crater (top) has a diameter of 32 km (20 mi.); Dominici crater (middle) has a diameter of 20 km (12 mi.)

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Tuesday, August 5, 2014

Rembrandt Impact Basin Mineralogical Map


The top image is a MASCS VIRS color composite of Rembrandt, Mercury's second largest impact basin. The bottom image is a MDIS color mosaic of the same area. Rembrandt's rim appears blue in both images, indicating low reflectance relative to its center in the VIRS image. Some small, fresh craters appear in yellow and are highly reflective in VIRS.

The VIRS composite shows hundreds of individual footprints tracks (minimum 100-200 m across and 3-4 km long) taken from different directions and altitudes. In locations where multiple footprints cover the same area, the footprint with the best illumination for mineralogical interpretation (usually the lowest incidence angle where shadows are minimized) is used for making the map.

Date Created: July 27, 2014
Instruments: Visible and Infrared Spectrograph (VIRS) of the Mercury Atmosphere and Surface Composition Spectrometer (MASCS) and Mercury Dual Imaging System (MDIS)
VIRS Color Composite Wavelengths: 575 nm as red, 415 nm/750 nm as green, 310 nm/390 nm as blue
MDIS Color Wavelengths: 1000nm as red, 750nm as green, 430 as blue
Center Latitude: -34.3°
Center Longitude: 87.2° E
Resolution: 1 km/pixel
Scale: Rembrandt is 715 km (444 mi.) in diameter

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Saturday, August 2, 2014

Messenger's Flyover Video


This movie consists of 214 images acquired by MESSENGER's Narrow Angle Camera (NAC) on June 8, 2014. The NAC field of view looks toward the horizon along the direction of spacecraft motion as the probe crossed the terminator into night. This view is what a traveler on the MESSENGER spacecraft might see during low-altitude operations over the next eight months. During the final phase of its mission, MESSENGER's science instruments will use low-altitude operations like this to explore the surface and subsurface of Mercury at unprecedented resolution.

The image frames were taken once per second while MESSENGER was at altitudes ranging from 115 to 165 kilometers, traveling at a speed of 3.7 kilometers per second relative to the surface. The movie is sped up by a factor of seven for ease of viewing. The images have resolutions ranging from 21 to 45 meters/pixel. Higher-resolution images of Mercury's surface are possible if the camera is pointed directly below the spacecraft rather than looking to the horizon, and such operations are the routine approach for low-altitude imaging. To observe an aerial view of MESSENGER's flight path, see PIA18637. To look closely at the flight path imagery, see PIA18636.

Date acquired: June 8, 2014
Image Mission Elapsed Time (MET): 44519827-44520005
Image ID: 6458912-6459090
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Initial Center Latitude: 77.2°
Initial Center Longitude: 78.1° E
Final Center Latitude: 79.2°
Final Center Longitude: 193.6° E
Resolution: 21 meters/pixel-45 meters/pixel
Scale: The first image is approximately 10.5 km (6.5 miles) across
Incidence Angle: 80.0°-87.6°
Emission Angle: 78.4°-83.5°
Phase Angle: 66.3°-66.4°

Video credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington